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The Vacuum Ultraviolet Spectra of Cyclohexane, Cyclohexene, 1,4-Cyclohexadiene, Isotetralin, and Several Methyl Substituted Analogs

Description: A paucity of literature exists on the Independent System analysis of adjacent, parallel transition dipoles. Applying this theory and certain spectral information semiemperical calculations were made to predict absorption profiles and band intensities. To aid in the assignment of the 7*+7 absorption bands it was necessary to obtain the vacuum ultraviolet spectra of cyclohexane and cyclohexene. Because the spectra of these molecules contained sharp, atomic-like absorption bands a Rydberg series c… more
Date: December 1974
Creator: Tidwell, Edgar Rhea
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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ESR Studies of Group IV Substituted Anilines

Description: The purpose of the investigation described herein was to investigate the degree of delocalization of the unpaired electron in ion radicals formed in the oxidation process of compounds with aromatic rings connected by means of various groups and atoms not entering the ring; then, to establish the relationship of coupling constants in radical cations with substituent σ values. The parent cation radical, in which the co-planar ion was derived from N,N-dimethylaniline, was selected in order to maxi… more
Date: June 1970
Creator: Wong, Pui-Suen
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Carbon-13-carbon-13 Coupling Constants in Fluorene and O-Methylbenzene Derivatives

Description: A model system to calculate single-path coupling constant was devised to see if the couplings are additive in a system which has a dual-pathway. The system chosen was o-methyl-13C-benzoic acid. Because of anomalies in the data, the series was extended. Hybridization of the label appeared to have relatively little effect, and the conformation of the substituents very important.
Date: August 1977
Creator: Kattner, Richard M.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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A Focus on Problems of National Interest in the College General Chemistry Laboratory: The Effects of the Problem-Oriented Method Compared with Those of the Traditional Approach

Description: Dealing with the college laboratory program in general chemistry, this study compares the effects of exercises based on current national problems with the effects of traditional laboratory exercises. The study has been prompted by the recent emphasis on topics of national interest in the undergraduate chemistry curriculum. These topics include air and water pollution, drug addiction and analysis, tetraethyl-lead additives, insecticides in the environment, and recycling of wastes. The relevant e… more
Date: December 1972
Creator: Neman, Robert Lynn
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Kinetics and Mechanism of Reactions of Disubstituted Octahedral Metal Carbonyls with Phosphorus Donor Ligands and Germanium Tetraiodide

Description: The kinetics and mechanism of the reactions of (tmpa)W-(CO)^ and (tmen)W(CO)^ (tmpa = N,N,N',N'-tetramethy1-1,3-diaminopropane and tmen = N,N,N1,N1-tetramethylethylenediamine) with four phosphorus donor ligands (triisopropyl phosphite, triphenyl phosphite, triphenylphosphine and "constrained phosphite", 4-methyl-2,6,7-trioxa-l-phosphabicylo[2.2.2]octane) in xylene have been investigated in detail. These reactions were found to take place by the ring-opening of the bidentate ligand in a reversib… more
Date: August 1976
Creator: Moradi-Araghi, Ahmad
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Bonding Studies in Group IV Substituted n,n-dimethylanilines

Description: The purpose of the present work is to study the effects of the trimethylsilyl and trimethylgermyl substituents on the N,N-dimethylamino ring system. Both ground and excited state interactions were studied and their magnitudes determined. The experimental data were then used in conjunction with molecular orbital calculations to differentiate among, and determine the importance of, d-p bonding, hyperconjugation or polarization of the trimethylsilyl group on the ground and excited state bonding.
Date: December 1971
Creator: Drews, Michael James
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Hyperconjugative Interactions in Silylanilines

Description: The purpose of the present work is to study the bonding interactions between the substituents and the ring π system for a series of ortho and para MeₙH₃₋ₙM (M = C or Si, n = 0-3) substituted N,N-dimethylaniline . Both ground and excited-state interactions were studied and their magnitudes determined. The experimental data were then used in conjunction with molecular orbital calculations to differentiate among inductive, hyperconjugative, and d-pπ interactions on the ground and excited states. O… more
Date: May 1975
Creator: Jung, Il Nam
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Studies of the Mechanisms of Reactions of Binary Metal Carbonyls

Description: A kinetic study of the reactions of Group VI-B hexacarbonyls with primary amine and halide ligands was undertaken in order to determine the possible mechanisms of these reactions. As well as the expected dissociative pathway, the reactions with the primary amines were seen to proceed by a concurrent pathway which was dependent upon the ligand concentration. Since nitrogen donor ligands are expected to be poor donor ligands, the mechanism proposed was a "dissociative interchange" mechanism which… more
Date: May 1977
Creator: Pardue, Jerry E.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Properties of Molecular Rydberg States

Description: Many of the bands in the vapor-phase far-ultraviolet absorption spectra of simple molecules can often be fit to mathematical progressions referred to as molecular Rydberg series. The name Rydberg arises from the similarity between the Rydberg formula for the atomic hydrogen spectrum and the formulae for the progressions found in molecular spectra. The theories of molecular Rydberg transitions and states are discussed in terms of the inferences that have been made in the past from the available … more
Date: December 1974
Creator: Scott, John Delmoth
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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The Crystal and Molecular Structures of Tri-(p-Fluorophenyl)-Amine and Tri-(p-Iodophenyl)-Amine

Description: Because of the need for data on the geometry of nitrogen in arylamines, the determination of the crystal and molecular structures of tri-(p-fluorophenyl)-amine (TFPA) and tri-(p-iodophenyl)-amine (TIPA) was undertaken as the subject of this dissertation.
Date: January 1970
Creator: Freeman, Gerald R. (Gerald Richard)
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Kinetic Studies and Vibrational Spectra of Disubstituted Metal Carbonyls

Description: The oxidative elimination reactions of (5-X-phen)Mo(C0)₄ (X = H, CH₃, Cl, NO₂; phen = o-phenanthroline) and (3,4,7,8-(CH₃)₄-phen)Mo(CO)₄ with mercuric chloride in acetone have been investigated. In these reactions, a carbon monoxide group is replaced by two univalent ligands, accompanied by the corresponding increase in coordination number and formal oxidation state of the central metal atom, to give products of the type, (X-phen)Mo(CO)₃(Cl)HgCl. With the exception of (3,4,7,8-(CH₃)₄-phen), the… more
Date: May 1972
Creator: Jernigan, Robert Thorne
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Infrared Studies of Group VIB metal Carbonyl Derivatives

Description: With three different proposals for the bonding in metal carbonyls, it was decided to look into the situation more thoroughly in order to see what other evidence was available to support or refute any of these ideas. It became obvious that a definite contradiction existed between the kinetic evidence of various metal carbonyls, and the concept of MC bond strengths as predicted by Cotton's theory.
Date: August 1971
Creator: Brown, Richard Arthur
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Halogenated 2-Oxetanones

Description: The purpose of this investigation is threefold: (1) to examine in detail the cycloaddition of halogenated ketenes and carbonyl compounds, (2) to study the decarboxylation of the resulting halogenated 2-oxetanones,and (3) to investigate the effect of halogens in the halogenated 2-oxetanones on the nucleophilic addition reaction.
Date: May 1973
Creator: Patel, Arvind D.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Electric Dichroism Spectroscopy in the Vacuum Ultraviolet

Description: When a molecule, which possess a permanent dipole moment is exposed to an intense electric field, its absorption spectrum may be altered. These alterations are manifest as shifts in energy and as changes in band shape and intensity. The electric dichroism of absorption bands can be used to probe the excited state that is formed when a molecule undergoes a transition. The properties that may be investigated include transition polarization, excited state dipole moment and mean polarizability, and… more
Date: May 1978
Creator: Causley, Gary C.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Organometallic Precursors to Cyclic Organosilanes

Description: This investigation deals with the preparations of cyclic organosilanes via two different types of organometallic precursors: borane adducts to chlorovinylsilanes and tertbutyllithium adducts to chlorovinylsilanes. The regiospecificity of the hydroboration of various types of boranes to chlorovinylsilanes was studied by three different methods. It was found that, by using bulky hydroborating agents, about 80% isomerically pure terminal borane adducts to chlorovinylsilanes could be obtained. Whil… more
Date: May 1977
Creator: Lim, Thomas Fay-Oy
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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